Figure 1

V rp1^f06715is new Vrp1 allele which exhibits severe somatic muscle fusion defects. (A-B, D-G) Stage 16 embryos were stained with antibodies against β3-Tubulin to visualize somatic muscles. (A) Wild type embryo (WT). (B) Df(2R)ED3943 mutant embryo with severe muscle fusion defects. Arrow indicates unfused cells. (C) Schematic representation of the Vrp1^f06715allele. The genomic location of the Vrp1 locus on 2R is indicated. mRNA representing exons and introns are shown as yellow and grey boxes respectively, and correspond to the longest predicted mRNA splice variant (CG13503-RA). The Vrp1^f06715allele has a piggyBac insertion (WHf06715) in the coding region of the 7^th intron, which disrupts gene function. Other genes in close proximity of the Vrp1 locus are illustrated with white boxes and their transcriptional direction with arrows (FlyBase [20]). (D) Wild type embryo (WT). (E) Vrp1^f06715mutant embryo (arrow indicates unfused cells). (F) Vrp1^f06715/Df(2R)ED3943 transheterozygous embryo displaying the same muscle fusion defects as Vrp1^f06715(arrow indicates unfused cells). (G) The Vrp1^f06715phenotype was reverted by precise excision of the WHf06715 piggyBac element.